FRIDAY, May 21 (HealthDay News) -- Among patients with non-Hodgkin's lymphoma, those who smoked, drank alcohol or were obese before receiving their diagnosis are more likely to die of the disease than others, researchers say.

For example, patients who smoked for at least 20 years are 76% more likely to die than those who never smoked. And obese patients -- those who are a step beyond overweight -- are 32% more likely to die than those of normal weight, according to the new study, led by Dr. James Cerhan, a cancer epidemiologist with the Mayo Clinic.

Alcohol use also boosts the risk of death, although drinking seems to actually lower the risk that people will develop non-Hodgkin's lymphoma in the first place, the study authors noted.

"This now raises the hypothesis that changing these behaviors after diagnosis might improve survival, but this needs to be tested in a clinical study," Cerhan said in a news release. "In the meantime, patients in active therapy should discuss any lifestyle changes with their health-care provider. Long-term survivors outside of therapy should consider the general public health guidelines that recommend smoking cessation, moderate or no alcohol use, and attaining a healthy weight."

The researchers came to their conclusions after studying 1,286 non-Hodgkin's lymphoma patients from several states. The patients completed health surveys shortly after they were diagnosed between 1998 and 2008, and they had recorded information about their height and weight a year before they were diagnosed.

By 2007, 34% of the patients had died, according to the report released online in advance of publication in an upcoming print issue of the journal Cancer.